Correlation of severity & clinical outcomes of COVID-19 with virus variants: A prospective, multicentre hospital network study

BACKGROUND OBJECTIVES

The clinical course of COVID-19 and its prognosis are influenced by both viral and host factors. The objectives of this study were to develop a nationwide platform to investigate the molecular epidemiology of SARS-CoV-2 (Severe acute respiratory syndrome Corona virus 2) and correlate the severity and clinical outcomes of COVID-19 with virus variants.

METHODS

A nationwide, longitudinal, prospective cohort study was conducted from September 2021 to December 2022 at 14 hospitals across the country that were linked to a viral sequencing laboratory under the Indian SARS-CoV-2 Genomics Consortium. All participants (18 yr and above) who attended the hospital with a suspicion of SARS-CoV-2 infection and tested positive by the reverse transcription-PCR method were included. The participant population consisted of both hospitalized as well as outpatients. Their clinical course and outcomes were studied prospectively. Nasopharyngeal samples collected were subjected to whole genome sequencing to detect SARS-CoV-2 variants.

RESULTS

Of the 4972 participants enrolled, 3397 provided samples for viral sequencing and 2723 samples were successfully sequenced. From this, the evolution of virus variants of concern including Omicron subvariants which emerged over time was observed and the same reported here. The mean age of the study participants was 41 yr and overall 49.3 per cent were female. The common symptoms were fever and cough and 32.5 per cent had comorbidities. Infection with the Delta variant evidently increased the risk of severe COVID-19 (adjusted odds ratio: 2.53, 95% confidence interval: 1.52, 4.2), while Omicron was milder independent of vaccination status. The independent risk factors for mortality were age >65 yr, presence of comorbidities and no vaccination.

INTERPRETATION CONCLUSIONS

The authors believe that this is a first-of-its-kind study in the country that provides real-time data of virus evolution from a pan-India network of hospitals closely linked to the genome sequencing laboratories. The severity of COVID-19 could be correlated with virus variants with Omicron being the milder variant.

Clinicopathological comparison of VHL expression as a prognostic tumor marker in renal cell carcinoma: A single center experience

AIM

To assess the VHL gene expression as a prognostic marker in Renal Cell Carcinoma (RCC) and compare it with clinicopathologic features.

MATERIALS AND METHODS

This retrospective observational study was conducted in the department of Urology and Renal Transplantation in Sri Ramachandra Institute of Higher Education and Research, Chennai from August 2016 to August 2018. Thirty patients who have undergone a radical/partial nephrectomy with biopsy proven histological diagnosis of RCC during the study period were included in the study. Data was analyzed using Statistical package for Social Sciences version 17.

RESULTS

A complete loss and retained VHL expression were noted in 60% and 40% of the RCC specimens. Association between smoking and VHL expression was found to be statistically significant. There was no statistical significance found between age group, sex, chief complaints, BMI. ECOG score, hypertension, family history, location of tumor, calcification, venous system or lymphnode involvement. However, rT staging, nature of lesion and cut surface, HPE type, pT staging, HPE grade, necrosis and lympho-vascular invasion were also found to be statistically significant.

CONCLUSION

Complete loss of VHL expression was noted in majority of the specimens that leads to the development of RCC. Smoking has been found to be statistically significant in tumors that retain VHL expression which may contributes to more aggressive form of tumor. Association between rT staging, nature of lesion and cut surface, HPE type, pT staging, HPE grade, necrosis and lympho-vascular invasion were also found to be statistically significant.

NWChem: Past, present, and future

Specialized computational chemistry packages have permanently reshaped the landscape of chemical and materials science by providing tools to support and guide experimental efforts and for the prediction of atomistic and electronic properties. In this regard, electronic structure packages have played a special role by using first-principle-driven methodologies to model complex chemical and materials processes. Over the past few decades, the rapid development of computing technologies and the tremendous increase in computational power have offered a unique chance to study complex transformations using sophisticated and predictive many-body techniques that describe correlated behavior of electrons in molecular and condensed phase systems at different levels of theory. In enabling these simulations, novel parallel algorithms have been able to take advantage of computational resources to address the polynomial scaling of electronic structure methods. In this paper, we briefly review the NWChem computational chemistry suite, including its history, design principles, parallel tools, current capabilities, outreach, and outlook.

Cardiovascular disease management in people with diabetes outside North America and Western Europe in 2006 and 2015

AIM

Optimal treatment of cardiovascular disease is essential to decrease mortality among people with diabetes, but information is limited on how actual treatment relates to guidelines. We analysed changes in therapeutic approaches to anti-hypertensive and lipid-lowering medications in people with Type 2 diabetes from 2006 and 2015.

METHODS

Summary data from clinical services in seven countries outside North America and Western Europe were collected for 39 684 people. Each site summarized individual-level data from outpatient medical records for 2006 and 2015. Data included: demographic information, blood pressure (BP), total cholesterol levels and percentage of people taking statins, anti-hypertensive medication (angiotensin-converting enzyme inhibitors, calcium channel blockers, angiotensin II receptor blockers, thiazide diuretics) and antiplatelet drugs.

RESULTS

From 2006 to 2015, mean cholesterol levels decreased in six of eight sites (range: -0.5 to -0.2), whereas the proportion with BP levels > 140/90 mmHg increased in seven of eight sites. Decreases in cholesterol paralleled increases in statin use (range: 3.1 to 47.0 percentage points). Overall, utilization of anti-hypertensive medication did not change. However, there was an increase in the use of angiotensin II receptor blockers and a decrease in angiotensin-converting enzyme inhibitors. The percentage of individuals receiving calcium channel blockers and aspirin remained unchanged.

CONCLUSIONS

Our findings indicate that control of cholesterol levels improved and coincided with increased use of statins. The percentage of people with BP > 140/90 mmHg was higher in 2015 than in 2006. Hypertension treatment shifted from using angiotensin-converting enzyme inhibitors to angiotensin II receptor blockers. Despite the potentially greater tolerability of angiotensin II receptor blockers, there was no associated improvement in BP levels.

Biostial iatrogenic coronary artery stenosis: a rare complication of aortic valve surgery successfully treated with percutaneous coronary stenting

A 66-year-old woman presented 4 months after conventional surgical aortic valve replacement with an acute coronary syndrome resulting from rare iatrogenic biostial left main and right coronary artery stenoses, which were successfully treated with percutaneous coronary stenting, optimized by intracoronary imaging.

Screening of Different Extracts of Marine Macro Green Algae for Larvicidal Activity against Dengue Fever Mosquito, <i>Aedes aegypti</i> (Diptera: Culiadae)

The present study larvicidal activities of hexane, chloroform, ethyl acetate, acetone and methanol extracts of Halimeda macroloba, Decsne, Caulerpa racemosa (Frosk) Weber-Van-Bosses and Ulva lactuca Lin, (Chlorophyceae) against Aedes aegypti. The marine macro green algae extracts were tested against early 4th instar larvae of A. aegypti using WHO protocol and concentrations of 200, 400, 600, 800 and 1000 ppm. The observed mortality was made 24 and 48 h after treatment, data was subjected to probit analysis to determine the lethal concentration (LC50 and LC90) of the treated larvae of the tested species.Among the tested extracts the maximum efficicacy was observed in the ethyl acetate extracts. The ethyl acetate extracts of the seaweeds showed the presence of terpenoids, tannins and phenolic compounds stronger than the other extracts. The results revealed that all the extracts showed varied levels of larvicidal activity against A. aegypti tested. However, the ethyl acetate extract of C. racemosa showed remarkable larvicidal activity against A. aegypti (LC50=579.9 and LC90=1255.4 ppm values at 24 h and LC50 =495.4 and LC90 =1073.9 ppm at 48 h) followed by U. lactuca (LC50=588.1 and LC90=1290.7 ppm values at 24 h, and LC50= 530.8 and LC90= 1160.0 ppm at 48 h), respectively. The lowest larval mortality was observed with hexane extract of H. macroloba against A. aegypti with values of LC50=1116.8 and LC90= 1824.5 ppm (after 24 h) and LC50=1059.9 and LC90=1768.3 ppm (after 24 h). The present studies indicate that the larvicidal activity and phytochemicals derived from the ethyl acetate extract of C. racemosa have the potential to be used as an ideal eco-friendly approach and effective mosquito vector control agent.

Screening of Different Extracts of Marine Macro Green Algae for Larvicidal Activity against Dengue Fever Mosquito, <i>Aedes aegypti</i> (Diptera: Culiadae)

The present study larvicidal activities of hexane, chloroform, ethyl acetate, acetone and methanol extracts of Halimeda macroloba, Decsne, Caulerpa racemosa (Frosk) Weber-Van-Bosses and Ulva lactuca Lin, (Chlorophyceae) against Aedes aegypti. The marine macro green algae extracts were tested against early 4th instar larvae of A. aegypti using WHO protocol and concentrations of 200, 400, 600, 800 and 1000 ppm. The observed mortality was made 24 and 48 h after treatment, data was subjected to probit analysis to determine the lethal concentration (LC50 and LC90) of the treated larvae of the tested species.Among the tested extracts the maximum efficicacy was observed in the ethyl acetate extracts. The ethyl acetate extracts of the seaweeds showed the presence of terpenoids, tannins and phenolic compounds stronger than the other extracts. The results revealed that all the extracts showed varied levels of larvicidal activity against A. aegypti tested. However, the ethyl acetate extract of C. racemosa showed remarkable larvicidal activity against A. aegypti (LC50=579.9 and LC90=1255.4 ppm values at 24 h and LC50 =495.4 and LC90 =1073.9 ppm at 48 h) followed by U. lactuca (LC50=588.1 and LC90=1290.7 ppm values at 24 h, and LC50= 530.8 and LC90= 1160.0 ppm at 48 h), respectively. The lowest larval mortality was observed with hexane extract of H. macroloba against A. aegypti with values of LC50=1116.8 and LC90= 1824.5 ppm (after 24 h) and LC50=1059.9 and LC90=1768.3 ppm (after 24 h). The present studies indicate that the larvicidal activity and phytochemicals derived from the ethyl acetate extract of C. racemosa have the potential to be used as an ideal eco-friendly approach and effective mosquito vector control agent.

Acute Internal Medicine Trainee Survey 2016

OBJECTIVES

To ascertain the views of current Acute Internal Medicine (AIM) trainees on the strengths and weakness of the specialty, their training programmes, practical procedures and the provision of training days.

METHODS

Online electronic survey circulated to all Higher Specialty Trainees (HST) in AIM. Participation was voluntary and all answers confidential. A total of 108 trainees responded.

RESULTS

There were respondents from across the United Kingdom. The majority of respondents are happy or quite happy with their training (61%), with 11% unhappy or very unhappy. The variety of workload (68%), specialty exposure (69%) and practical procedures (67%) were strengths while lack of respect from other specialties (55%) and rota gaps (59%) remain significant problems. 53% of respondents feel they are expected to cover more rota gaps than their GIM colleagues, and 54% trainees feel they do not get a session a week allocated to them for specialist skill training/admin. Only 33% of trainees expect to get dedicated leadership and/or management training during their programme, and a large proportion of trainees (78%) feel that some form of ultrasound training should be a core part of the curriculum. Despite the difficulties, 85% of respondents would recommend AIM as a specialty.

CONCLUSIONS

This survey highlights some of the positives and negatives of training in AIM, and highlights areas where potential improvements to programmes could be made. Comparison of the data with 2015 shows small improvements in a number of areas, but still some significant concerns remain. The findings were fed back to the Training Committee in March.

Engineering 3D Nanoplasmonic Assemblies for High Performance Spectroscopic Sensing

We demonstrate the fabrication of plasmonic sensors that comprise gold nanopillar arrays exhibiting high surface areas, and narrow gaps, through self-assembly of amphiphilic diblock copolymer micelles on silicon substrates. Silicon nanopillars with high integrity over arbitrary large areas are obtained using copolymer micelles as lithographic templates. The gaps between metal features are controlled by varying the thickness of the evaporated gold. The resulting gold metal nanopillar arrays exhibit an engineered surface topography, together with uniform and controlled separations down to sub-10 nm suitable for highly sensitive detection of molecular analytes by Surface Enhanced Raman Spectroscopy (SERS). The significance of the approach is demonstrated through the control exercised at each step, including template preparation and pattern-transfer steps. The approach is a promising means to address trade-offs between resolutions, throughput, and performance in the fabrication of nanoplasmonic assemblies for sensing applications.

Antibacterial Activity of <i>Ulva fasciata</i> against Multidrug Resistant Bacterial Strains

The present study was conducted to evaluate the antibacterial activity of different organic solvent increasing polarity viz., hexane, chloroform, ethyl acetate, acetone and methanol extracts of Ulva fasciata (Chlorophyceae) were collected from Kanniyakummari, Gulf of Mannar biosphere Reserve, Tamilnadu, India. Marine green algae extracts of U. fasciata against multi-drug resistant standard and clinical bacterial strains viz., Bacillus subtilis, Streptococcus pyogenes, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhimurium, Vibrio cholerae, Shigella flexneri, Proteus mirabilis and P. vulgaris. The ethyl acetate extracts of U. fasciata showed highest antibacterial activity against all the bacterial strains tested. The mean zone of inhibition produced by the extracts in disc diffusion assays were ranged from 7.1 mm to 15.0 mm. The Minimum Inhibitory Concentrations (MIC) were between 125 μg/ml and 500 μg/ml, while the Minimum Bactericidal Concentrations (MBC) were between 250 μg/ml and 1000 μg/ml. The highest mean of zone inhibition (15.0 mm) and lowest MIC (125 μg/ml) and MBC (250 μg/ml) values were observed in ethyl acetate extract of U. fasciata against B. subtilis. The ethyl acetate extract of the U. fasciata showed the presence of phytochemicals, terpenoids, tannins and phenolic compounds in U. fasciata than the other solvents extracts. The present results of the ethyl acetate extract of U. fasciata can be used as an antibacterial substance for the treatment of multi drug resistant bacterial infections

Antibacterial Activity of Ulva fasciata against Multidrug Resistant Bacterial Strains

The present study was conducted to evaluate the antibacterial activity of different organic solvent increasing polarity viz., hexane, chloroform, ethyl acetate, acetone and methanol extracts of Ulva fasciata (Chlorophyceae) were collected from Kanniyakummari, Gulf of Mannar biosphere Reserve, Tamilnadu, India. Marine green algae extracts of U. fasciata against multi-drug resistant standard and clinical bacterial strains viz., Bacillus subtilis, Streptococcus pyogenes, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhimurium, Vibrio cholerae, Shigella flexneri, Proteus mirabilis and P. vulgaris. The ethyl acetate extracts of U. fasciata showed highest antibacterial activity against all the bacterial strains tested. The mean zone of inhibition produced by the extracts in disc diffusion assays were ranged from 7.1 mm to 15.0 mm. The Minimum Inhibitory Concentrations (MIC) were between 125 μg/ml and 500 μg/ml, while the Minimum Bactericidal Concentrations (MBC) were between 250 μg/ml and 1000 μg/ml. The highest mean of zone inhibition (15.0 mm) and lowest MIC (125 μg/ml) and MBC (250 μg/ml) values were observed in ethyl acetate extract of U. fasciata against B. subtilis. The ethyl acetate extract of the U. fasciata showed the presence of phytochemicals, terpenoids, tannins and phenolic compounds in U. fasciata than the other solvents extracts. The present results of the ethyl acetate extract of U. fasciata can be used as an antibacterial substance for the treatment of multi drug resistant bacterial infections

Determination of the antioxidant capacity, total phenolic and flavonoid contents of seeds from three commercial varieties of culinary dates

Date seeds are a major waste product of the date industry that could offer potentially valuable material for the production of useful food ingredients. The aim of the present study was to investigate the seeds of three date varieties of the UK market (Deglet Nour, Khouat Allig, and Zahidi) for their proximate composition, total phenolic (TPC), total flavonoid (TFC) contents and total antioxidant capacity (TAC) with a view to their eventual industrial application. Carbohydrates were present in the highest concentrations varying between 74.13 and 76.54 g 100 g-1 of date seed powder (DSP) on dry weight (DW) basis, followed in descending order by fats (7.64-8.84 g 100 g-1) and proteins (4.35-5.51 g 100 g-1). Potassium was found in high amounts with values ranging between 280.55 and 293.13 mg 100 g-1. The majority of the total phenolic content (2058-2984 mg GAE 100 g-1) was assumed to be composed of flavonoids (1271-1932 mg CAE 100 g-1). These families of dietary phenolics may be the major ones responsible for the high antioxidant capacity reported in date seeds, which varied from 12540 and 27699 µmol TE 100 g-1. These results suggest that date seeds can be considered a potential raw material for natural, active ingredients for food applications as well as an unexplored source of novel nutraceuticals and dietary supplements.

Predictive value of atrial high-rate episodes for arterial stiffness and endothelial dysfunction in dual-chamber pacemaker patients

BACKGROUND

Various pacing studies have demonstrated an association between right ventricular pacing (RVp) and atrial fibrillation (AF), even after preserving atrioventricular (AV) synchrony. We aimed to assess the interaction between arterial stiffness, endothelial function and atrial high-rate episodes (AHRE) in patients with dual-chamber pacemakers.

METHODS

We studied 101 patients with dual-chamber pacemakers incorporated with sophisticated AF detection and therapy algorithms. Macrovascular endothelial dysfunction (ED) was measured by the relative change in aortic augmentation index (AIx), using carotid artery applanation tonometry in response to inhaled salbutamol and sublingual glyceryl trinitrate. Microvascular ED was measured by cutaneous laser Doppler flowmetry (LDF) in response to acetylcholine (Ach, endothelium dependent) and sodium nitroprusside (SNP, endothelium independent). Arterial stiffness was measured using carotid-femoral pulse wave velocity (PWVcf). 'Reservoir pressure' (Pr, MATLAB) describes the aortic 'cushioning' properties.

RESULTS

Mean age of the cohort was 72.1 ± 10.8 years; men (n = 69) 68.3%. Of 101 dual-chamber pacemaker patients, 23.8% (n = 24) had AHRE detected on the baseline pacemaker interrogation. PP, PWVcf and Pr were significantly higher in patients with AHRE compared with those without AHRE. The change in AIx with salbutamol (∆% AIx Sal) and acetylcholine-induced changes in LDF (Δ%LDF Ach) were lower in patients with AHRE compared with those without AHRE. In patients with AHRE, significant correlations were observed between%Vp and Δ%LDF Ach (P = 0.03) as well as between PP and Δ%LDF Ach (P = 0.05). On multivariate analysis, PP, Pr, PWVcf and ∆% AIx Sal remained as independent predictors of AHRE.

CONCLUSION

In patients with dual-chamber pacemakers, both higher arterial stiffness and greater endothelial dysfunction independently predicted AHRE, irrespective of the degree (or mode) of pacing. Arterial stiffness and endothelial dysfunction may potentially contribute to the perpetuation of atrial arrhythmias beyond the adverse effects of ventricular pacing alone.

Weil's disease presenting as atypical pneumonia

Leptospirosis is a disease caused by spp. Leptospira, also known as Weil's disease if it manifests with jaundice. It can be associated with respiratory, renal, hepatic and haematological complications and most importantly carries a high mortality when untreated. We describe a case of a 53 year old man presenting with myalgia and fever in whom the diagnosis of leptospirosis was not initially considered. Following a deterioration in his condition a careful history revealed an apparent brief exposure to animal urine and subsequent grossly positive Leptospira serology. Treatment of his condition led to complete resolution after a brief stay on the intensive care unit. This case highlights the atypical nature of a presentation of Leptospirosis, its respiratory complications, and importance of serological testing in its diagnosis.

Prognostic role of plasma von Willebrand factor and soluble E-selectin levels for future cardiovascular events in a 'real-world' community cohort of patients with atrial fibrillation

BACKGROUND

Endothelial damage/dysfunction may contribute to a prothrombotic state in patients with atrial fibrillation (AF) and the increased risk of thromboembolism and cardiovascular events. Raised plasma von Willebrand factor (vWf), an established marker of endothelial damage/dysfunction, has been associated with stroke and vascular events, at least in a clinical trial population. Soluble E-selectin (sE-sel) is another biomarker of endothelial activation/dysfunction, with more limited data on prognostic outcomes in AF.

OBJECTIVE

To assess the relationship between the levels of vWf, sE-sel and clinical adverse outcomes (including stroke, MI and all-cause mortality) in a 'real-world' community cohort of patients with AF.

METHODS

We studied 423 patients (mean age 72·7 ± 8·4 years, 55·6% male) with nonvalvular AF, with a median follow-up of 19 (9-31) months. Plasma vWf and sE-sel levels were measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS

There were 94 clinical adverse events (22·2%) observed during a median follow-up of 19 months. Patients with clinical events had significantly higher vWf (P < 0·001) and sE-sel levels at baseline (P < 0·001) compared with those who were event free. Kaplan-Meir analyses demonstrated that more clinical adverse events occurred in the upper tertile of vWf [upper vs. lowest tertile, RR 3·8, 95% CI (2·63-5·57), P < 0·001; upper vs. middle tertile, RR 10·5, 95% CI (5·33-20·60), P < 0·001]. Similarly, the highest tertile of sE-sel was associated with more adverse events [upper vs. lowest tertile, RR 3·7, 95% CI (2·51-5·31), P < 0·001; upper vs. middle tertile, RR 6·5, 95% CI (3·56-11·91), P < 0·001].

CONCLUSION

High plasma vWf and soluble E-selectin levels are associated with an increased risk of clinical adverse events (acute myocardial infarction, ischaemic stroke and all-cause mortality) in 'real-world' patients with AF. These soluble biomarkers may potentially aid clinical risk stratification in this common arrhythmia.

Viewpoint: norovirus outbreak on the AMU: a lesson in shared clinical leadership

Three times a year, the first Wednesday of the month heralds a changeover of junior doctors within our hospital. This year, the first Wednesday in December provided a different kind of challenge. The voice on the phone confirmed the words that no one wanted to hear: "You have three confirmed cases of Norovirus and you have to close to new admissions".

Primary intrarenal teratoma in an adult: A case report and review of literature

A 35-year-old male presented with left loin pain. On evaluation, he was diagnosed to have a left renal lower polar mass. He underwent partial nephrectomy. The histopathological examination was suggestive of teratoma of the kidney. We present this case, as intrarenal teratomas in adults are extremely rare and only a very few cases are reported in literature.

Assessment of left atrial volume: a focus on echocardiographic methods and clinical implications

Left atrial enlargement is an important predictor of cardiovascular events such as atrial fibrillation, stroke, heart failure and mortality. A number of methods of left atrial size assessment by echocardiography have been reported, from the simple antero-posterior diameter in the parasternal long axis view to the more complex ellipsoid, area-length and Simpson's method of estimating left atrial volume. These different methods of left atrial size assessment, their clinical implications and some common pitfalls are discussed in this review.

Safety and cost-effectiveness of same day permanent pacemaker implantation

An overnight stay after permanent pacemaker implantation has major cost implications for healthcare systems. Same day pacing could be effective in alleviating this. We evaluated our elective same day pacing practice to determine safety and cost-effectiveness. A total of 780 patients were scheduled for elective new permanent pacemaker implantation as a same day procedure at the University Hospital, North Staffordshire, from April 2001 to December 2006. The mean age +/- SEM of the cohort was 73.8 +/- 0.4 years (464 men and 316 women). Single-chamber devices were implanted in 272 (27 atrial and 245 ventricular) and dual chamber in 508 patients. Vascular access was by the subclavian vein in 431 patients and the cephalic vein in 349. Preimplant intravenous antibiotics were administered to 28% and perioperative antibiotics to the remainder; all patients received oral antibiotics after implantation. Of the 780 patients, 41 (5.3%) required an in-hospital stay after implantation because of hematoma formation in 12, pneumothorax in 3, social reasons for 7, observation at the physicians request but no complication for 13, angina in 3, arrhythmia in 1, and warfarin therapy in 2. Immediate complications (<24 hours) occurred in 6 patients and early complications (>24 hours to 6 weeks) developed in 17. Of the 780 patients, 94 had died at mean follow-up of 2.4 +/- 0.1 years; none were related to pacemaker implantation. An overnight stay at our hospital costs pound203.60 ( approximately US$305). From November 2005 to November 2006, 109 patients underwent same day implantation, resulting in a cost saving of pound22,192.40 ( approximately US$34,500). In conclusion, same day permanent pacemaker implantation was feasible, safe, and cost-effective. It was associated with a low prevalence of complications and only a few patients required an overnight stay.

Association of methylenetetrahydrofolate reductase gene polymorphisms & colorectal cancer in India

BACKGROUND & OBJECTIVES

Methylenetetrahydrofolate reductase (MTHFR) is a critical enzyme in folate metabolism and involved in DNA synthesis, DNA repair and DNA methylation. The two common functional polymorphisms of MTHFR, 677 C-->T and 1298 A-->C have shown to impact several diseases including cancer. This case-control study was undertaken to analyse the association of the MTHFR gene polymorphisms 677 C-->T and 1298 A-->C and risk of colorectal cancer (CRC).

METHODS

One hundred patients with a confirmed histopathologic diagnosis of CRC and 86 age and gender matched controls with no history of cancer were taken for this study. DNA was isolated from peripheral blood samples and the genotypes were determined by PCR-RFLP. The risk association was estimated by compounding odds ratio (OR) with 95 per cent confidence interval (CI).

RESULTS

Genotype frequency of MTHFR 677 CC, CT and TT were 76.7, 22.1 and 1.16 per cent in controls, and 74, 25 and 1.0 per cent among patients. The 'T' allele frequency was 12.21 and 13.5 per cent in controls and patients respectively. The genotype frequency of MTHFR 1298 AA, AC, and CC were 25.6, 58.1 and 16.3 per cent for controls and 22, 70 and 8 per cent for patents respectively. The 'C' allele frequency for 1298 A-->C was 43.0 and 45.3 per cent respectively for controls and patients. The OR for 677 CT was 1.18 (95% CI 0.59-2.32, P = 0.642), OR for 1298 AC was 1.68 (95% CI 0.92-3.08, P = 0.092) and OR for 1298 CC was 0.45 (95% CI 0.18-1.12, P = 0.081). The OR for the combined heterozygous state (677 CT and 1298 AC) was 1.18 (95% CI 0.52-2.64, P =0.697).

INTERPRETATION & CONCLUSION

The frequency of the MTHFR 677 TT genotype is rare as compared to 1298 CC genotype in the population studied. There was no association between 677 C-->T and 1298 A-->C polymorphisms and risk of CRC either individually or in combination. The homozygous state for 1298 A-->C polymorphism appears to slightly lower risk of CRC. This needs to be confirmed with a larger sample size.

Unusual presentation of thyrotoxicosis as complete heart block and renal failure: a case report

Introduction

Thyrotoxicosis is a clinical entity often very difficult to diagnose without biochemical confirmation as its clinical features can be highly varied. The most common cardiac manifestations of thyrotoxicosis are resting sinus tachycardia, supraventricular tachycardia including atrial fibrillation and atrial flutter with or without cardiac failure. Bradycardia and atrio-ventricular conduction defects are very uncommon in thyrotoxicosis.

Case presentation

We report the case of a 59-year-old Caucasian man presenting with progressive weight loss, abnormal liver function, acute renal failure and complete heart block due to thyrotoxicosis.

Conclusion

Thyrotoxicosis should be considered as a possible diagnosis in patients with bradycardia and heart blocks associated with abnormal symptoms like weight loss. Nevertheless, the clinical, electrophysiological and biochemical abnormalities associated with thyrotoxicosis may be completely reversible restoring euthyroid state.

Thrombosis prophylaxis in patients with ischaemic (cardioembolic) stroke. How long is long enough?

Cardioembolism accounts for approximately 20% of ischaemic strokes, and is associated with high mortality and propensity to recurrences. Approximately, 30% of ischaemic strokes remain cryptogenic despite improved imaging modalities and technological improvements to identify their cause. Of the long list of various cardiac conditions associated with an increased risk of cardioembolic strokes, non-valvular atrial fibrillation is the most common cause. Unsurprisingly, the stroke risk associated with these conditions is highly variable and non-homogenous, with many risk factors additive to the overall risk profile. Treatment with vitamin K-antagonists substantially reduces the long-term complications associated with cardioembolism in some high-risk patients, for example, in atrial fibrillation. Careful selection of antithrombotic drug regime needs to be carried out in patients individually to minimise the risk of bleeding encountered with such therapy. Apart from atrial fibrillation, there is relatively limited evidence for the role of antithrombotic therapy for other cardiac conditions associated with cardioembolism and how long one should treat.

Assessment of endothelial (dys)function in atrial fibrillation

Atrial fibrillation (AF) is associated with an increased risk of mortality and morbidity from stroke and thromboembolism. Endothelial damage or dysfunction may contribute to this increased risk of thromboembolism via the mediation of a prothrombotic or hypercoagulable state. However, the precise pathophysiological mechanism(s) relating endothelial (dys)function to AF and thromboembolism are yet to be fully elucidated. This review article aims to provide a comprehensive overview of endothelial (dys)function and AF, as well as the merits and limitations of the different methods used to assess endothelial function in AF.

High-technology materials based on modified polysaccharides

Polysaccharides are abundantly available from farm, forest, and microbial resources. They are used in myriad applications. It has been established in the authors' laboratory that their performance is enhanced considerably on purification, grafting by polyacrylamide (PAM), and subsequent hydrolysis as well as cationization. The most significant performance is enhanced in flocculation where it has been found that the modified polysaccharides outperform existing flocculants in national and international markets. Similar effects are observed in their performance in turbulent drag reduction (DR), percolation, and rheology. The present article outlines the details of materials, mechanisms, and practical applications of these novel materials.

Tunable, high aspect ratio pillars on diverse substrates using copolymer micelle lithography: an interesting platform for applications

We demonstrate the use of copolymer micelle lithography using polystyrene-block-poly(2-vinylpyridine) reverse micelle thin films in their as-coated form to create nanopillars with tunable dimensions and spacing, on different substrates such as silicon, silicon oxide, silicon nitride and quartz. The promise of the approach as a versatile application oriented platform is highlighted by demonstrating its utility for creating super-hydrophobic surfaces, fabrication of nanoporous polymeric membranes, and controlling the areal density of physical vapor deposition derived titanium nitride nanostructures.

Acute ST-elevation myocardial infarction secondary to paradoxical embolism

Acute ST-elevation myocardial infarction (STEMI) is a life threatening condition usually caused by rupture of an atheromatous plaque in the coronary arteries. Other causes, such as septic emboli, cholesterol emboli and cocaine abuse have been reported. We report a case of acute STEMI in a young female without any vascular risk factors due to a presumptive paradoxical embolism via a secundum atrial septal defect (ASD). Young patients without vascular risk factors presenting with acute myocardial infarction should be investigated to exclude an underlying cause of their myocardial infarction, such as a paradoxical embolus.

The systematic tunability of nanoparticle dimensions through the controlled loading of surface-deposited diblock copolymer micelles

The continuous tunability of iron oxide nanoparticle dimensions is demonstrated using the pH controlled loading of ferric nitrate from aqueous solution into polystyrene-block-polyacrylic acid reverse micelles deposited on a silicon substrate. Quasi-hexagonally ordered two-dimensional arrays of iron oxide nanoparticles with a systematic tunability of particle heights in the sub-10 nm regime and a constant periodicity are obtained and characterized with atomic force microscopy and x-ray photoelectron spectroscopy.